This invention relates to an exit guiding system which is provided in an access or passageway to a fire exit for indicating a guiding direction toward the exit.
In conventional exit guiding devices provided on walls around fire exits for indicating the positions of the fire exits, messages indicative of the exit or symbol marks are indicated by illuminating built-in light sources. It has been proved that these indications by light become hard to see at the time of fire, due to smoke caused by the fire. To solve this problem, it has been proposed that a flashing light device such as a xenon tube be provided in the exit guiding device and the xenon tube be driven to emit light at the time of fire for making the indication visible even in the smoke. Or, there is another proposal to indicate the exit to those who have poor sight. In this proposal, a voice outputting device is provided in the exit guiding device, so that it may give a vocal message for escape guidance at the time of fire, at a volume of, for example, 90dB or more.
However, these escape guiding devices have the disadvantage that not only those who have poor sight but also normal persons may possibly be guided by the flashing light or vocal messages, to exits which have already become dangerous. This occurs if guidance by the flashing light or vocal message is continued even after the exits or the accesses to the exits are already dangerous due to permeation of smoke.